The first Verification Page (Cookie, Redirect) - How?

[datiswous]

http://www.phpbook.net/age-validation-form-in-php.html
https://discussion.dreamhost.com/thread-32395.html
http://www.youtube.com/watch?v=NDUwoH-Bid8

I didn't test them.
But you should search yourself. And this one is probably complete:
http://codecanyon.net/item/agelock-age-v...pt/4931493

(of course with MySQL it would be much easier)

I don't know what MySQL has to do with it and how that would be easier. I think it would make it more complicated, to use a database with a simple age verification script..